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• 作者：Weiß ; Katharina ; Kö ; ppe ; Ralf ; Schnö ; ckel ; Hansgeorg
• 关键词：FT/ICR-MS ; Gallium cluster ; Jellium model ; LDI
• 刊名：International Journal of Mass Spectrometry
• 出版年：2002
• 出版时间：March 15, 2002
• 年：2002
• 卷：214
• 期：3
• 页码：383-395
• 全文大小：424 K

文摘

The metalloid cluster [Ga₁₉(C(SiMe₃)₃)₆][Li₂Br(THF)₆] was studied by Fourier-transform ion cyclotron resonance-mass spectrometry (FT/ICR-MS). The spectrum obtained by laser desorption ionization (LDI) is dominated by pure gallium cluster anions Ga_n⁻ with n ranging up to 50 and mixed gallium–silicon cluster anions Ga_nSi⁻, Ga_nSi₂⁻, and Ga_nSi₃⁻ with n ranging up to 43. A maximum of the cluster abundance is observed for Ga₁₃⁻ and Ga₁₂Si⁻. These experimental results exhibit for the first time the formation of large pure and silicon-doped gallium clusters starting from a molecular compound. They are discussed in terms of the precursor’s structure and the simplified predictions of the jellium model. DFT calculations were employed to further evaluate the electronic properties of these anionic clusters, the results of which show that Ga₁₃⁻ favors a regular bicapped pentagonal prism (D_5h) as well as Ga₁₂Si⁻, Si being located in the center of the cluster.